Headlights on even when switch is off.

[Luis Guillen Jr]

I picked up a trailer 2 days ago that used the 4 prong light cord. Now with no trailer the headlights are on whenever truck is running no matter where the light selector is set. Did I short something out when I plugged the trailer in?

 

[ibike]

That would be your daytime running lights. Do they shut off when you shut down the engine?

 

[crash68]

Did I short something out when I plugged the trailer in?

Highly unlikely as the circuits to the trailer pins are isolated via relay and individual fuses.

That would be your daytime running lights.

DRLs should only illuminate when the vehicle is in gear. If the transmission is in park or the parking brake is set the DRLs don't turn on.

 

[ibike]

Highly unlikely as the circuits to the trailer pins are isolated via relay and individual fuses.

DRLs should only illuminate when the vehicle is in gear. If the transmission is in park or the parking brake is set the DRLs don't turn on.

One would think that, but when I start mine the drl’s are on. All the vehicles I’ve had as you say drl’s come on when in gear and when the e-break is on they go off. Not my Ram. Engine running drl’s are on.

 

[Justthebutler]

Check your connector, if there is corrosion, dirt, water, etc. It could be shorting and back feeding power to your lights. You live in Florida, so there could be some salt water corrosion.

 

[brian42]

Another vote for your the headlights are set as the DRLs, which is an easy check. You can go into your settings and de-select that option to see if that fixes the issue.